Forget Glenn Beck’s right-wing politics and conspiracy theories for a moment if you can: The launch today of his daily show on his new GBTV Web platform (at 5 PM ET/2 PM PT) makes this “a watershed day for the media/television industry,” BTIG analyst Rich Greenfield says. Media execs, he adds, “should be very afraid” because Beck may demonstrate how content creators can “build their brands outside the traditional content gatekeeper system with greater creative freedom and the potential for generating far more wealth over time.” Beck’s followers are giving him a strong start. The Wall Street Journalsays that 230,000 people have already subscribed to GBTV — potentially giving it a bigger audience than Oprah Winfrey’s cable network OWN, which averages 156,000 viewers. GBTV costs $4.95 a month just for Beck’s two-hour daily show and $9.95 for Beck plus other programming. That suggests the former Fox News star will generate at least $13.7M a year from subscribers — and probably a lot more: At least 80,000 people already pay $9.95 a month for his “Insider” service that includes Beck’s daily radio show. All told, Greenfield figures subscribers will pay $27M a year for GBTV. And that’s before the enterprise lines up advertising. If the numbers pan out, then media execs won’t be the only people who’ll be afraid of GBTV.